Cumulative demand meter



July 19, 1938- w. c. WAGNER CUMULTIVE DEMAND METER Filed July 24, 1934 8.Sheets-Sheet l lo Il/l X ul 0 emnnnummuv u \4 July 19, 3938- W. c. WAGNER CUMULATIVE DEMAND METER 8 Sheets-Sheet 2 Filed July 24, 1934 MUT/V555.'

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CUMULATIVE DEMAND METER I Filed July 24, 1934 8 Sheets-Sheet 3- F/G2. F763.

CUMULATIVE DEMAND METER Filed July 24, 1954 8 Sheets-Sheet 4 July 19, 1938.

W. C. WAGNER GUMULATIVE DEMAND METER Filed July 24, 1934 8 Sheets-Sheet 5 ooohoooonoogoooobooh F/Q. Z,

my@ @WWW 19, 1938., W. c. WAGNER CUMULATIVE DEMAND METER Filed July 24, 1954 8 Sheets-Sheet 6 July 19 w38 w. c. WAGNER CUMULATIVE DEMAND METER 8 Shees-SheeiI 7 Filed July 24, 1954 @SMM July 19, 193s. W, WAGNER www CUMULATIVE DEMAND METER Filed July 24, 1934 8 Sheets-Sheet 8 Patented July 19, 1938 UNITED STATES PATENT OFFICE This invention relates to improvements in maximum demand meters, including watthour demand registers and the indicating and graphic types of demand meters. One object ofthe present invention is to increase the reliability of maximum demand measurements in the simpler forms of demand meters and registers, making ypossible not only improved performance in'the measurement of maximum demands in electric, gas, steam and other metering for whichmeters of this type are commonly used, but also permitting the extension of the use of the simpler forms of', demand meters into' fields which now require the,-

The invention'however, is equally applicable to demand meters of the latter classiiication, for

which it permits a reduction inthe time requiredto determine the maximum demand reading.

The application of my invention has made possible the development of a new combination which greatly simplies the construction of demand meters and their application to metering installations, particularly in stations and for the customers of public utilities.

My invention will be described rst in its simplest form in which it is applied to indicating electrical watthour demand meters and registers, after which its application to the graphic forms, together with the new graphic cumulative demand registers and printing maximum demand registers will also be described.

The conventional arrangement for the indicating type of maximum demand meter has certain disadvantages, the most important of which are errors in reading due to parallax, and tothe complete obliteration of the reading after the meter has been reset. For this reason such' maximum demand meters are a prolic cause of disagreements between customers 'and the utility companies which supply them.

The invention forming the subject matter of this application causes the resetting of the meter to add the reading for the maximum demand to the reading of a dial or dials provided for the purpose. At each succeeding reading period when the meter is reset, thereading is added to the preceding reading of these dials, and hence thereading used for billing purposes represents the difference' between the present and preceding reading.

By this arrangement, any error in the reading for one period is automatically compensated in the reading for the succeeding period. Also, in the event of disputes in regard to the alleged maximum demand indication for a preceding the same meter.

f vention consists of discouraging attempts on the use of more-expensive demand measuring devices.

period, a definite4 check of the reading for that period is possible'by reference to the pointer up to the time that the dial is again advanced by resetting the meter at the following reading period.

The present invention is applicable to watthour-demand meters which combine the kilowatthour registration with the maximum demand indication, and to indicating demand meters which show a reading of maximum demand but do not include the measurement of kilowatt-hours in Another advantage of my inpart of unscrupulous consumers to attempt to reduce the maximum demand indication. Any complete `or partial motion in returning the pointer to zero results in increasing the reading of the "cumulative dial, and hence each successive attempt to do this will increase the accumulated reading of the cumulative dial at the time of the next reading at the end of the billing period.

The indicating watt hour-demand register is well known in the metering art, and no originality is claimed in regard to the maximum demand indicating device, except in combination with the cumulative dial' feature which is described in detail.

In the following descriptions reference will be made to the following schematic and diagrammatic drawings forming part hereof and in which Fig. 1 shows a typical indicating maximum-de- ;mand. register with the conventional mainmum demand pointer and the cumulative maximum demand recording mechanism in accordance with my invention.

Fig. 1A is a side view showing a resetting de- `vice which is applicable to the construction shown in Fig. 1.

Fig. 1B, Sheet 8, shows in detail a cumulative mechanism in which the resetting of the pointez' causes the demand to be registered on the cumulative dials.

Fig. 1C, Sheet 8, shows in detail an alternative construction in which the cumulative dials are actuatedby the meter, and resetting of the pointer causes it to be placed in position for actuating the cumulative dials in accordance with the demand of the succeeding period.

Fig. 2 shows the face of a watthour-demand register in which the cumulative recording dials are distinguished by having their numerals inscribed on circular disks, and the register face serves as a suitable mask to facilitate reading.

Fig. 3 shows the face of a watthour-demand .55

and scale have been entirely eliminated. Thel cumulative dials indicate the sum of maximum i demands in successive reading periods.

Fig. 6 shows a typical indicating demand meter with the cumulative feature similar to Fig. 2.

, Fig. l shows a typical graphic watthourdemand meter to which the cumulative feature has been applied.

Fig. 8 shows the new combination of a simplined graphic demand indicating mechanism and a cumulative demand mechanism within the register of a meter.

Fig. 8A is a sectional view taken on the line SA-BA of Fig. 8.

Fig. 9 shows a structural variation of the graphic cumulative watthour-demand register,

including a torque device for reducing the mechanical load, which is driven by themeter element.

Fig. l0 shows a structural variation of Fig. 8, and represents a somewhat simpler construction of the graphic demand mechanismV within the register of the meter. i

Fig. 10A is a side view of the chart mechanism shown in Fig. 10.

Fig. 11 shows a graphic cumulative watthourdemand meter with a circular chart mounted on the register face. r

Fig. 12 shows the combination of a cumulative printing demand meter with a cumulative dial for indicating the maximum demand. y

Fig. 12A shows a detail on the line IZA-IZA of Fig. 12.

Fig. 13 shows a printing type of demand meter in which the printed record shows the individual period demands, together with the cumulative dial for giving the maximum demand reading.

Fig. 14 shows a detail on the line Id-lii in Fig. 13 and Fig. 15 is a perspective view of one of the typewheels.

In Fig. 1 a conventional watthour meter disk I drives the well known watthour meter dials 2 through suitable gearing 3. 4 and 5 and shafts 6, l and 8. At the same time disk I, through gearing 3, I0 and II, and shafts 6, l, l2, I3 and 9 drives dog lli against friction pointer I5. Timing motor IBthrough shafts I'I and I8 and' gears I9 and 20 operates cam 23 which controls the periodic release of clutch 2l between shafts I3 and 9, by means of lever 33 and return spring 34. This causes dog It and shaft 9 to be returnedto the startingposition by spring 22. The forward movement of dog I4 pushes friction pointer I5 over scale 24, and pointer I5 remains at the highest reading to which it has been driven during any of the regular periods as controlled by timing motor I6. Pointer I5 therefore, serves to indicate the maximum load which has passed claimed for it and the multiplicity of possible tion is illustrated at 255 in Fig. 7.

aiaaevv structural variations except in combination with l the cumulative device to be described.

Attached to pointer i5 is ratchet drive 32 which drives ratchet wheel 25, (indicated in Fig. 1 and shown in Fig. 1B, Sheet 8) and suitable gearing 2t, cumulative dials El, and their ratio gears 23.

Fig. 1C', Sheet 8, shows an alternative construction, in which the forward motion of pointer I5 drives ratchet wheel 25 through ratchet 32, and cumulative dials 2l through gearing 23 and 28. When pointer i5 is reset to zero, ratchet 32 is released, causing it to assume a new position `in relation to ratchet wheel 25, thus again permitting pointer l5 to drive cumulative dials 2l to the position of maximum demand for the succeeding period. In general the construction of Fig. 1B is preferred because it imposes no additional mechanical load on the meter element, thereby eliminating possible inaccuracies in the measurement of kilowatt-hours, particularly during periods of light load.

Another structural variation of the principle of operation, consists of a ball clutch in place of ratchet 32 and ratchet wheel 25. I This construc- It is obvious that this arrangement may be used interchangeably with the ratchet arrangement shown in the other figures.

The conventional demand register is reset to zero at the end of the billing period by an externally operated scalable resetting device inthe meter cover. This permits friction pointer I5 to be reset to zero. Referring to Fig. 1A, the iinger piece 6l on the outside of the cover operates the resetting pusher through a ratchet device `29, so that it can turn the pusher in one direction only, and the pusher 3l is yieldingly mounted so that it can pass the pointer I5 when the latter reaches its stop d. A similar device is illustrated in Fig. 8A. They dier from the conventional reset in that a ratchet drive is added. This prevents partial resetting which would result in incorrect indication of the cumulative dials. For use uwith the cumulative dial, it is possible also to adapt the resetting device so as to require several turns of the resetting lever or hand piece for one revolution of the resetting pusher. This is accomplished by inserting gears ,of the desired ratio between the lever and tained through openings 35 in the register face.

This arrangement together with arrows 36, facilitates the reading of the cumulative dials 21| and serves also to distinguish these dials from meter dials 2 which give the energy consumption. If desired however, meter dials 2 may be of similar construction to the cumulative dials shown at 2li..

In Fig. 3 the design of the cumulative dials 212 includes the cyclometer design which is well known to the art, and commonly used in counters of various kinds. It differs only to the ex- `tent of the required detailed design for gearing 26|. It is apparent that meter dials 2 may also be of the cyclometer type if desired.

With the cumulative dial; scale 24 and pointer are no longer required for obtaining an accurate demand reading, but may be of value in giving an approximate but immediate indication of maximum demand. It is possible therefore to make these accessories less prominent than in the conventional type of demand register. Such an arrangement is shown in Fig. 4 in which friction lever |5| does not move over a scale, but through gearing 37, drives pointer |52 which moves over scale 24|.

Fig. 5 shows the entire elimination of the demand scale and its associated pointer.

Fig. 6 shows a typical indicating demand meter. The demand meter is controlled by cam 38 and contact 39 within the watthour meter. Contact 39 closes a circuit from source 40 to operating coil 4| which attracts armature 42, and through lever and dog arrangement 43 actuates ratchet wheel 44 which, through suitable gearing 45 causes dog I4 to advance and to push friction pointer l5 over scale 24. Timing motor I6 through gearing i9 and 20 and shafts and |8 operates cam 23, which in turn causes lever 33 to demesh gears 45 at desired intervals. It is apparent that an arrangement similar to clutch 2| in Fig. 1 is interchangeable with the sliding gear arrangernentofd Fig. 6. No originality is claimed for this part of the mechanism which is typical of indicating demand meters in common use to-day. The cumulative dial arrangement as described in detail for Fig. 1 is` arranged to operate by the resetting of pointer l5, and the operation of the cumulative feature is entirely in accord with the preceding description. It is evident also that the structural variations in regard to the detailed method of operation, as for example in Fig. 1C, the diierent forms of dial faces of Figs. 1 to 5., and the ball clutch of Fig. 7, are allequally applicable to indicating demand meters.

For use with customers of large energy requirements, graphic or printing demand meters are generally used by utilities for determining the maximum demand for billing purposes and to record the characteristics of the load. The routine inspection of some types of charts for finding the maximum demand requires consid! erable time', and a saving in time results by combining the cumulative feature with the graphic demand mechanism. The maximum demand reading will then be equally reliable, and may be even more accurate than one obtained by an inspection of the chart. Fig. '7 shows a graphic demand meter equipped with a cumulative dial. No originality is claimed for the graphic demand meter except in combination with the cumulative dial.

While some graphic demand meters are used on services for which it is necessary to determine the demand for every demand interval, in the great majority of cases only the maximum demand is required to be of the requisite accuracy for billing purposes.` The remainder of the record serves only as an index to the general load requirements. Since the cumulative dial provides an accurate reading of the maximum demand, it is possible to so simplify and reduce in size graphic and printing demand mechanisms that they may be constructed as a 4part of the meter register, instead of requiring a graphic watthour-demand meter of distinctly different design from that used when no demand measurement is required. It becomes possible therefore to produce a graphic cumulative watthour demand register which may be applied in place of the regular watthour register. With my invention therefore, it becomes possible to replace the ordinary register of an installed meter with one which provides a cumulative dial for the maximum demand reading, and also a graphic or printed record of other demands, as compared with the entire replacement of the meter or the use of a separate demand meter, which is necessary with equipment which has been availablel heretofore.

Fig. 8 shows such an arrangement developed along the general lines of the watthour-demand registers of Figs. 1 to 5 inclusive; and this arrangement utilizes various parts of the demand register mechanism in conjunction with the graphicchart equipment which is included within the register.

The cumulative register is similar to that described in detail in Fig. 1 except that it is actu-s ated from arm or lever 53 instead of from pusher pointer I5. Attachedto shaft 9 is pinion gear |42 which engages rack 53, which in turn carries stylus 54. Timing motor I6 through suitable gearing 41 drives the chart control bobbin 52. The latter is designed to drive perforated. chart 55| at the desired constant speed. Bobbin 52, through suitable means, as a belt and pulley arrangement 48 and 4G, drives also re-roll 49. Chart 55| is prevented from unrolling too rapidly by retaining spring 66 on chart supply spool 5|.

In operation, pinion gear 42 resets at the end of every demand interval by the operation of clutch 2| and spring 223 which pulls rack 53 against stop 58 and returns stylus 54 to the zero position. It is evident that the amount of motion of the stylus during each demand interval depends upon the energy supplied during that demand interval, and with the chart moving at constant speed a record similar to that shown on chart 55| is produced. Pin 51 on gear 42 pushes pin 56` on friction lever |53, whose position at the end of a given period will correspond to the maximum motion of gear |42 in any 'demand interval during the period. Friction lever |53 controls cumulative dials 21|, through ratchet wheel 25 and gearing 25. Resetting of the cumulative dials is accomplished by returning pin 566 on friction lever i53 to the zero position. This may be done by hand or through hand operated means to be presently described. Thisvmotion of friction lever |53 through pins 56 and 5'| also actuates gear i 42, which is permitted to move by the slipping of clutch 2|, and returns rack 53 and stylus 54 to the zero position. In the graphic registers it is not necessary to provide for resetting of the cumulative dials from-the outside of the meter cover, which is removed for changing the chart. If desired however such means may be provided, and are shown in detail in section in Fig. 8A.

The resetting device in the meter cover as shown in Fig. 8A is applicable to the forms of cumulative dials as shown in Figs. l to 13 inclu sive. It differs from that used in ordinary watthour demand meters in that a ratchet 29 is provided whereby the motion of the resetting pusher is limited to the direction required for resetting. This eifectively prevents the resetting device from being operated so as to produce a fictitious reading. In resetting, knurled knob 6l outside or" meter cover 59 operates ratchet wheel 68 and ratchet pawl 29 attached to disk 59, which carries resetting lever 3|. The latter is pivoted and is held in its normal position against a stop by a spring, which permits it to assume the position shown dotted when pin it@ has reached the limit oi its travel at the zero position and in that zero position the resetting lever 3i passes the pin itt. Knurled knob il is slotted to receive latch llt, which is hinged to stud li which is mounted in a fixed position on cover 59. In the position for normal meter operation latch l@ is closed and ts into slot i3 in knurled knob El, with a seal applied through sealing hole l?. it is apparent that the latch cannot be closed and seal applied except when knob @l is in the position where the resetting' operation has been completed. To operate, the reset latch l@ is opened and .knurled knob 6l is turned through a complete revolution, when latch l@ may again be closed. t is possible also to provide for a resetting operation of several revolutions of knob @l by interposing ratio gears between knob tl and disk t. The spirit and principle of this invention includes all means of resetting a demand meter by means oi a reset capable of operation in one direction only, and of making it mandatory to complete the resetting operation before the reset device may be resealed. It is apparent that many detailed varia` tions may be made in the mechanical arrangement, ratchet 29 may be a ball clutch, and disk @il may consist of other suitable means for carrying resetting lever 3 i, as shown in Fig. 7.

in the design of Fig. 8 the operation or the demand mechanism may introduce an appreciable burden in relation to the available torque or the watthour meter. A development which overcomes this objection is shown in Fig. 9. Here the motion of gear ifi?? is transmitted to rack "oil to which is attached spring 226i which tends to pull rack 53 and stylus Enti toward the full-scale position, but is permitted to do so only in so far as worm drive i@ will permit gear lili to turn. Resetting of stylus tl to zero at te end oi every demand interval is accomplished by the operation of solenoid t@ acting on core @l which moves rack 53 against the action of spring 2lb?, and slip clutch 'Zi, through gear i132 and shaft $3. Solenoid til is operated by contacts @t and operated by the timing cams i3d and The operation oi' the cumulative dials is the same as for Fig. 8, ekcept that the resetting motion is opposite in direction by the reversal of ratchet 32. lThis permits the zero position or stylus 5S to be on the let hand side of the chart.

Fig. 10 shows a simplied construction in the driving member for the stylus over the chart. Stylus arm lili is attached to shaft 9 and carries stylus tti which moves over chart in the form of an arc. Its motion also pushes friction lever H53 by means of stud itt. The cumulative dial, general re-roll, and chart arrangements of Fig. 8 are applicable, except that a fiat surface t5 in Fig. 10A is provided to serve as a base'against Which'stylus li may mark chart 553.

Fig. ll shows the application of a circular chart to the cumulative watthour-demand register face. Timing motor it drives shaft 'lf3 through gearing Zii, and chart 554i is attached to a disk at the end of shaft l5 by knurled knob l5, so that chart itl will rotate in accordance with elapsed time. Stylus arm M2 is attached to shaft 9, either dim rectly or through suitable gear reduction, and hence the relative motion of stylus 5&2 and chart 55d will result in a'. chart similar to that indicated in Fig. l1.

Further applications are possible with the cumulative register by applying a printing arareaal? rangement and tape instead of the graphic chart. Fig. l2 shows this arrangement. Printing dies lt are driven from shaft i3 through shaftsl and 88 and gears il and ill. Since shaft i3 is geared to the watthour meter element the rotation of dies 'it is a measure of the energy consumption. At desired time intervals cams dit and 64 close contacts 63 and t2, thus energizing solenoid 8i from source iii for a den'ite period of short duration. Solenoid 3i attracts its core 80, which carries platen B2 and presses paper tape 555 and inking ribbon di against the numerals on the periphery of printing dies l@ thus printing a number on paper tape tt. Paper tape 555 and inking ribbon 9i are moved at constant speed by spools e3 and 9i?, which are being driven by timing motor i6 through gearing @il and 2i?, and shafts lili, i8 and li. Guides 35 retain the paper and inking tapes in their proper positions as they are gradually unroiled from their retaining spools tf and Zit. lThe numerals printed on the paper tape are cumulative, and the demands oi successive demand intervals are obtained by subtracting successive readings. A

At the same time shaft i3 also drives pusher lever itt through shaft ii and clutch il, and the cumulative dial mechanism, which has been described previously, provides ior obtaining the maximum demand reading. A variant in design of the clutch release is incorporated in Fig. 12, in that the periodic release oi the clutch 2i is accomplished by solenoid di y means of core il@ to which resetting lever 33t is attached. In order to obtain a sharp impression oi the numerals on the tape, platen B is arranged so that actual printing is accomplished by the momentum oi platen t? and core li, Fig. 12A, thus permitting platen 32 to move back slightly after the initial impulse of coil Si. The return oi the platen is facilitated by spring dt.

ln Fig. 13, provision is rnade for the return of the printing dies to the zero position at the end of each demand interval. The printed record on the tape, therefore, shows the individual demands without the necessity for a subtraction. This is accomplished by demeshing gears @d on shaft iii@ from gears iii' at the end of every demand interval, after the printing operation is completed. The return to zero of the printing dies may be accomplished by means of a heart-shaped cam, well known to the art and commonly used in rotating standards as a means of zero reset; or by weighting the printing dies iti, Fig. l5 so that when they are free to move they will return to the zero position. In the design shown, shaft lil@ is carried in frame attached to core tl of solenoid 92, whose operation is controlled by contact 93, which is closed by the return motion of core t@ of solenoid di. Contact 93 is normally held in the open position by spring et, and the movable arm of contact 93 carries lever iid, which is shown in the normal inoperative position. At the end of every demand interval when core 8B moves upward, projection Q9 strikes lever 6; which is free to move to permit projection 99 to pass on its upward stroke. On the return stroke, however, projection 99 strikes lever 95, and by means of stop mi and movable contact arm 91 closes contact 93, thus energizing coil 92 and permitting the printing dies to reset.

Many variations in detailed design and construction features are possiblel to accomplish the results desired which are new to the metering art and which represent the spirit and intent of my invention. While the description has covered in UJI detail the application of the principles involved to electric meters, it is apparent that they are equally applicable to meters designed for the measurement of gas, Water, steam or condensate by merely driving shafts l and i3 from the rotating member of the respective meters and providing electrical source @iii Jfor operating timing motor it and the electrical printing or reset arrangements in Figs. 9, l2, and 13. It is apparent also that in all cases timing motor i5 may be a spring motor in which case electrical source lil is not required for Figs. l to 5, 7, 8, l and 1l.

The designs shown in Figs. l2 and 13 have a further application in that the printing mechanism may be arranged to provide successive readings at much longer intervals than the usual demand intervals of from 5 to 60 minutes. It is evident that with suitable additional reduction gearing for shaft il successive readings mayt be at intervals of a day, Week or month if desired, in which case the printed tape will give the energy consumption during such periods. The cumulative demand feature is not necessary for this purpose, but can be applied if the reading of maximum demand is also desired.

It will be obvious to those skilled in the art that modiiications may be made in details of construction and arrangement without departing from the spirit of the invention which is not limited in respect to such mattersor otherwise than the prior art and the appended claims may require.

I claim:

l. In a'meter, a case, a pointer lever, a reset device comprising a pusher, means whereby said pusher may yieldingly contact and pass the pointer lever in its zero position, means whereby said pusher may be operated in one direction only, manual means for operating said pusher from the outside of the case, and means for sealing said external operating means.

2. In a meter, a case surrounding and enclosing the operating elements of said meter, a pointer lever, a reset device comprising a pusher, means whereby said pusher may yieldingly contact and pass the pointer lever in its zero position, means whereby said pusher may be operated in one direction only, and manual means for operating said pusher from the outside of the case.

3. In a removable register for a Watthour demand meter, means for indicating cumulatively the maximum demand made in each of a number of successive periods, and means for indicating the successive demand readings on a chart arranged within the removable register.y

4. An electric demand meter including a pusher element for indicating independently the demand in successive periods, means for causing a return of said pusher element at the end of each such period, a sweephand operated by said pusher element to the point of its greatest movement, a reset lever, the operation of which is necessary for setting back said sweephand to zero, an integrator operated by said sweephand in its setting back movement to indicate the extent of said movement, means for sealing said lreset lever in an inactive position, means for preventing the movement of said lever except inv the re-setting direction, and means for releasing said reset lever from said sweephand when said sweephand reaches the zero posittion.

5. An electric demand meter including a, pusher element for indicating independently the demand in successive periods, means for causing a-return of said pusher element at the end of each such period, a sweephand operated by said pusher element to the point of its greatest movement, a reset lever, the operation of which is necessary for setting back said sweephand to zero, an

' integrator operated by said sweephand in its setting back movement to indicate the extent of said movement, means for preventing the movement of said lever except in the re-setting direction, and means for releasing said reset lever from said sweephand when said sweephand reaches the zero position. f

WALTER C. WAGNER. 

